This invention relates to a method and article of manufacture for removing paper which is adhered to a surface including wallpaper, signs or the like.
Presently, wallpaper generally is attached to a wall by means of a starch-based adhesive such as wheat paste, or the like. Periodically, the wallpaper is removed prior to applying a new wallpaper or a paint coating to the wall. The removal of old wallpaper is a difficult and time consuming job since the paste generally has aged over a period of years and treatment of the old adhesive must pass through the paper prior to reaching the adhesive. At the present time, this is usually accomplished by applying steam through the paper to wet the adhesive and weaken it to the point that the wallpaper can be scraped from the wall. This technique is undesirable from a number of standpoints. First, the technique requires specialized apparatus and is relatively expensive. In addition, when the steam penetrates the wallpaper, it picks up odorous deposits accumulated in the wallpaper and spreads these deposits over other portions of the interior of the building.
It has also been proposed, for example, in U.S. Pat. No. 2,607,359, to provide a composition containing an enzyme, water and a wetting agent and applying it to the exposed surface of the glued paper, which enzyme degrades the adhesive. For example, with a starch-based adhesive, it has been proposed to employ a diastatic type enzyme. Similarly, when the adhesive is a proteinaceous glue, it has been proposed to employ a proteolytic enzyme in the composition. While this procedure has certain advantages over steaming, problems have been encountered with the specific enzyme compositions employed therein. A major problem results from the fact that when the enzymes are mixed with aqueous solutions or contacted with moisture, enzyme degradation is initiated so that it becomes necessary to apply all of the solution to the paper within a relatively short period of time after mixing or contact with moisture, or to employ excessively large concentration of enzyme to assure the presence of the requisite concentration of actual enzyme. Compositions comprising enzymes packaged in aqueous solutions have extremely short shelf lives or required excessive concentrations of expensive enzymes which has prevented their commercial utilization.
It would be highly desirable to provide a means for utilizing an enzyme composition for removing paper adhered to a surface which requires the use of only relatively low concentrations of enzymes, particularly when removing wallpaper adhered with the commonly employed starch-based adhesives. Furthermore, it would be desirable to provide an enzyme-based paper removal composition having a long shelf life so that active paper removal compositions can be prepared and used at the convenience of the practitioner.